High-speed dynamo-electric machine for continuous current



A ril 1927.

p M. KOSTENKO ET AL.

HIGH SPEED DYNANO ELECTRIC MACHINE FOR CONTINUOUS CURRENT Filed March 19. 1923 2 Shoots-Shout 1 Apnl M. KOSTENKO ET AL HIGH SPEED DYNAMO ELECTRIC MACHINE FOR CONTINUOUS CURRENT Filed March 19, 1 2 Shoots-Sheet 2 Patented Apr. 12,1927.

UNITED STATES PATENT 1 OFFICE.

MICHAEL KOSTENKO AND NICOLAS JAPOLSKY, OF LONDON, ENGLAND.

HIGH-SPEED DYNAMO-ELECTRIC MACHINE FOR CONTINUOUS CURRENT.

Application filed March 19, 1923, Serial No. 626,132, and in Switzerland February 5, 1923.

l'ligh speed alternating current machines having a small number of poles can be constructed for obtaining very high outputs; machines for other hand for very great peripheral speeds and great outputs have hitherto not been known. Further, it has hitherto not been possible to collect considerable power through stationary brushes resting on a rela lively movable commutator.

The subject of the present invention is a high speed dynamoelectric machine having a small nmnber o't' poles and yielding a large continuous current. The induced part of the machine is stationary, while the inducing part rotates. The machine has two collectors, one is provided with rings and the other with segn'ients. Both collectors rotate at a speed, which is smaller than that o't the inductor, the armature winding bang connected to the rings of the ring collector by brushes, and eaclrof the said ringsloeing connected to a plurality of the segments of the segment collector or commutator, the arrangement being such that the stationary brushes, which rest on the relatively moving; segment commutator collect continuous current.

The number of inductor poles is smaller than the number of brushes on the segn'ient commutator and, the arrangement is such that the number of'revolutions of the inductor during" unittime multiplied by the number of poles of the said inductor, equals the number of revolutions of the corm'nutator per unit time multiplied by the number ot brushes on the segment commutator.

Various coi'istriurtional forms of the 111 vention are diagrammatically illustrated in the accompanying drawings, in which Fig. 1 indicates a preferred form'of the connections between the stator and the ring collector or slip rings.

Fig. 2 shows one form of the complete machine.

F igs. 3, 4, 5 and 6 show various modified forms of the machine.

In the constructional iorm shown in Fig. 2 R is the inducing part (inductor) of the machine having two main poles N, S while S is the induced part or armature of the machine. The ring collector Q has 16 rings, which are marked 1, II XVI. On the periphery of the segment commutator 1e are provided six stationary brushes C, D, E, F, G and H. It is necessary for the continuous current on the two collectors to rotate at a speed which is smaller than that of the inductor, both speeds having a definite relation to each other, so that if in is the number of revolutions of the inductor and m; the number 01 revolutions of the collectors, P the number of poles of the inductor, B the number oi brushes, then:

In the example shown in Fig. 2-, it is therefore necessary for the collectors to rotate at a speed which is equal to one-third oi? the speed of the inductor. The armature S has 8 windings. The ends and the middle points of each winding are each con nected to one of the sixteen rings I-XVI of the ring collector Q. Each ring of the collector is connected to three segments of the commutator K. These segments are 120 apart. Thus, for instance, the ring I is connected to the segments 1, 1", 1'.

The ring 11 is connected to 2, 2", 2'. The brushes C, D, E on the one hand and F, Ur,

H on the other hand are at a definite mo ment connected to the same ring. Thus three each can be connected together as shown in the diagram.

The continuous current required for exsion of a separate excitation for the two auxiliary poles n and s. The exciter m works on the two main poles of the inductor, while the exciter E works on the auxiliary poles at and s. The inductor winding S of the exciter E, is connected in series with the main current. Thus for a constant speed of the exciter E the electromotive force of the latter is almost proportional to the current of the main circuit.

In theconstructional form shown in F ig. 4 the armature S has two independent windings O and 0 Each of these windings is connected to a corresponding ring collector Q, and Q The collector Q, is also connected to the segment commutator K while the collector Q, is connected to the segment commutator K The number of poles of the inductor is in each case assumed to be two, while the number of brushes in contact with the segment commutator is four for each of these commutators. Thus the speed of the collectors Q and K and th t of the collectors Q and K will be half the speed of the inductor.

In the diagram shown in Fig. 4 the two conmiutators K and K are connected to each other in series. By this means the machine will give double the voltage that can be given by a single comn'iutator. If a independent windings were placed on the armature S, a voltage VzaXV would be obtained at the terminals of the machine, in which case V would represent the voltage of a single commutator. The commutators might also be connected in parallel. lVit-h the construction described, between two consecutive segments ot' the commutator, there may be connected up a portion only of an armature conductor. This is of particular advantage in the case of high speed machines giving off very high voltage, in which the voltage included in each wire of the armature may exceed that permissiljde between two commutator segments. ()n the other hand as the armature stationary, the connection of the armature to the ring collector may be made through the ventilating passages a, Z), 0, (Z, 6, as shown in Fig. 1.

Fig. 5 diagrammatically indicates a dynamoelectric installation for converting alternating current into direct current, or vice versa.

S is a stationary armature whose winding is connected on the one hand to the secondary winding TV, of a transformer T, and on the other hand, as described above, to the rings of the collector Q.

The collector Q is secured to the commutator K and is mechanically driven by means of the rotor R.

The connnutator K supplies continuous current to the direct current mains.

The electromot-ive force between the difi'erent points of the winding 0 is produced by the moving magnetic iield due to the rotor R.

This rotor R is magnetized by continuous current supplied through slip-rings from the direct current mains.

The alternating current mains are connected to the primary winding W', of the transformer T.

Fig. 6 diagrammatically indicates another form of dynamo-electric installation for converting alternating current into direct current or vice versa.

This machine works in a similar way to the machine shown in Fig. 5, but in this case the armature S has two separate windings, one W being connected to the alternating current terminals of the machine, while the other V is connected to the collector Q and thence through the commutator K to the continuous current terminals.

The rotor R is magnetized, as before, by continuous current supplied through sliprings from the direct current mains.

The collector Q and commutator K are mechanically driven by a synchronous motor L which is driven by alternating current supplied from the alternating current mains. The number of poles of the motor L is equal to the number of brushes of the commutator ii. The direct current for the magnets oi the motor L is supplied from the direct current mains.

Since the windings \V, and TV for the alternating and direct currents are separate trom one another, the transformer T of Fig. is dispensed with, as the necessary increase or reduction in the alternating current voltage can be obtained by varying the number oi? bars in the winding The high speed machines permit of an intense utilization of the copper, and they work with a. very high eiliciency. Therei rom it results that the efiiciency of the arrangements described will be a very high one.

"What we claim is A high speed dynamo electric machine for continuous current of the type generator, motor, converter, comprising a stationary armature with ventilating passages, a r0tat ing inductor, two commut-ators rigidly connccted with each other, one formed of a set of insulated rings and the other of a set of insulated segments, leads connecting the rings with the corresponding segments, and two sets of brushes, one set contacting with the insulated rings and connected with the armature inding by leads passing through said passages in the armature, and the other set contacting with the commutator segments, and means for rotating the commutator at a speed which is a sub-multiple of that of the inductor, so that the two sets of brushes act to transmit direct current.

in, testimony whereof we hereunto afiix our signatures.

MICHAEL KOSTENKO. NICOLAS JAPOLSKY. 

